Locomotive draft arrangement



Feb. 5, 19 46. B HARRls ET -2,394,17 3

LOCOMOTIVE DRAFT ARRANGEMENT v INVENTORS I E ALBERT B. HARP S y GRANVILLE [:4.BAKR

THE/P ATTOR NEY Feb. 5, 1946.

A. B. HARRIS ET AL LOCOMQTIVE DRAFT ARRANGEMENT Filed July 26, 1945 2 Sheets-Sheet 2 INVENTORS. ALBERT B. HARP/6 BY GRANVILLE M.BAKER THE/R AYTTOPNE Y Patented Feb. 5, 1946 2,394,173 LOCOMOTIVE nnAFT ARRANGEMENT A bert B.- H r s Wayne, d Grat M! Baker, Fl t-B Miqh- Application J uly 26, 1943, Serial No. 496,248

s Q s es- (a; can) Qu invention ertains. 29th? lse t s tu e, and itarrsnssments er n'qqm vs an mor erticu arlyt senleanin s r arrest rrangements ther o 44mm; 1. eriqus ar s arres in a ra me t have be n used n. l qt res; n na t founda ion o th sna l; re i r ins s in genera se- The lo ng. 9 uc s k. r net in y t mer and. i pa le e s f qaeet l am shis. c n t n b t s" the sac and cites causes. e ens e de on he bustion gases throughthe netting which avoids hot spots and lengthens the life of the netting;

It is also an object of our invention to provide an improved self-cleaning" spark ar'restor of a simple rugged construction which will be reliable and positive in operation.

lit is a further objector our invention to provide a spark arrestor arrangement which will be self-cleaning either under the condition wherein the draft is induced by pulsations of exhaust steam or by live steam froma blower.

Further objects and advantages are within the scope of the invention, such as relate to the arrangement, operation and function of the related elements of the'structure, to various details of construction and to combinations of parts, elements, per se, and to economies of manufacture and numerous other'features aswill be apparent from a consideration of the specification in conjunction with the drawings disclosing specific embodiments of the inventionj in which:

' Fig. 1 is a vertical sectional'view taken axially into the front end of a"locomotive provided with an improved spark arrestor arrangement, in accordance with our invention, and partially broken away; U

Fig. 2 is a plan view of the table plate portion of Fig. 1, projected directly up for clearness and, partially broken away at the ends;

Fig. 3 is an enlarged fragmentary sectional view on line 3'3 in Fig.1, and partially broken away, showing the end of the netting'agit'ator' shaft and leverarm;

Fig. 4 is a cress sectional view through the table plate, on line 4-4 in Fig. 2, showing the auxiliary opening, netting and valve plate 5 is a fragmentaryenlarged view on line E sl: and

E s- 6 s Viewv simi ar to Fi s 1 are win di ferent. emb diment o o r scr en a atlas Referring more specifically to Fig. 1 of th drawings we have illustratively disclosed our improved self -cleaning spark arrestor arrangement as installed in a locomotive havinga'well known type offront end generally known as the master mechanics front end arrangementyalthough it will be apparent that our invention is readily adaptablet'q various 'other'types of arrangements of the deflector walls and smoke box, either in the front end or otherwise. i

' In Fig. 1 the smoke box iii of such a locomotive is shown enclosed by a front end wall I I attached to the front end of the boiler shell 13 the pe ripheral walls of which further enclose the smoke box on the top, bottom and sides, and having a down-set portion 14 in the front end of'the upper side thereof. A smoke stack l5, provided for discharging'combustion gases from the smoke box, projects down into the upper side thereof in alignment with an exhaust' nozzle I1 which enters the" smoke box through the lower wall, in a; well known manner. 'The lower end of the smoke stack I5 flares out to a larger diameter and is spaced suitably from the upper end of the exhaust nozzle I! to receive exhaust steam from the engine (not shown) forinducing a draft to flow through the'smoke box Ill and up the stack I 5, in 'a well known manner. Also such locomotives are provided with suitable deflector means or bafile'walls IQ for enclosing a space around the lower end of the smoke stack and causing the combustion gases to flow toward the front end of the smoke box and then to return through an opening 20, see Fig. 5, 00 enter the lower end of the smoke stack through the segregated smoke stack space. Thewall under the stack is a substantially horizontal" plate 2|, termed a table plate," which extends transversely across the smoke box, and'through which the upper end of the exhaust nozzle I1 passes being secured snugly therein, in a well known manner. Mounted in the smoke stack space is the usual blower ring tube 23 securedin' concentric relation around the upper'end'of the exhaust nozzle, as-by brackets 25 'risingfrom the upper side "of the table plate 2i, for projecting jets of live steam up into the stack from orifices 21 to induce sufficient draft either when the engine is not operating, or supplementalto the exhaust steam under certain conditions.

To "restrain cinders and other fire bearing particles from passing from the smoke box into and Qulfof 'thesmoke stack; it has long been customary "to the opening 20, in the front s il-492 f the d fle t?!" W sui a e re arrei tor newness uc fsett n mav b s ee sea sense were i 'tsb e ren me arena. .1. .9 she t. its. shatters 1. .3 eqsesee s i he P esent in sn n' th rk en i wire, q i e h r r asedge of the plate.

opening 20 in the front portion of the deflector walls is provided with a spark arrestor netting 29, the marginal edgesor side members 31 of which repose loosely in a frame33, as shown in Fig. 5, and which extends around the edges of the opening so that the netting has freedom for substantial movement laterally. In its nearest position toward the smoke stack, the netting abuts a stop flange 35 from whence it falls back against a back flange 31 giving it suflicient movement for violent agitation to dislodge cinders and solid particles, which are broken up and pass through the screen. To provide sufficiently positive and violent agitation of the netting to clear the obstructions therefrom, we provide a vane 4| which is movably disposed in the path of the combustion gases for movement therewith, for actuating agitator means to throw the netting back and forth. A draft plate 41 is provided one edge of which is hinged, or pivotally secured, under and along the front edge of the table plate 21, as by a hinge pin 43 and hinge bracket 45 at the ends of the draft plate. This suspends the other or lower swinging edge of the draft plate 4| in a position exposed to the pulsations-of combustion gases drawn through under the table plate by the successive discharges of exhaust steam up the stack.

Agitator means for vibrating the netting comprises a shaft 41 extending transversely across under the front side of the netting and having the ends rotatively supported journalled in bearing brackets 49 at the sides of the opening in the deflector plates. Secured on the shaft 41 in' any suitable manner, as by a key, is an agitator crank having a cam portion 53 projecting upwardly along the side member 3] of the netting screen to be engaged and thrown forward by angular movements of the shaft. Two or more such cam agitators 53 are provided at the sides of as many movable netting screens as are to be vibrated. For actuation of each agitator cam 53, a lever arm 55 projects down from each agitator crank 5| to a position for operative connection with the lower swinging edge of the draft plate, as by a link 51 connecting pivotally at one end, which may be split, to the lower end of the lever by a pivot pin 59 passing therethrough, and having the other end connected pivotally to the swinging edge of the draft plate, as by a pivot pin Bl passing into a pivot bracket 63 on the When a high velocity pulsation of combustion gases passes forward under the table plate, the lower edge of the draft plate swings forward pushing the levers 55 and the cam agitators 53 to the positions represented by dotted lines, and throwing the netting 29 back in its frame, against stop flange 35. When the high velocity pulsation of combustion gases subsides, the agitator parts fall back to the full line position, permitting the netting to fall back and strike against the back flange 31. This cycle of operations, being repeated in rapid succession with the discharges of exhaust steam, shakes obstructions from the spark arrestor netting.

Under conditions when the blower 23 is in operation projecting live steam to induce a draft, and intermittent exhaust pulsations are absent or not present in suflicient intensity to shake the netting clean, itmay occur that the spark arrestor netting 29 becomes so badly obstructed that draft is retarded and the operation of the blower only results in creating a partial vacuum of considerable magnitude in the space around the smoke stack. At the same time the pressure in the lower portion of the smoke box is such, or the pressure differential between the two spaces is such, that thenetting'is held continuously to its position nearest the smoke stack.

' To release the pressure differential, and to provide draft and free steaming under such conditions, we provide auxiliary netting B5 in combination with a valve or flow restricting means 61, which normally closes the auxiliary netting but which opens in response to an abnormal pressure differential. For this purpose, an auxiliary opening 69 is provided in the deflector wall structure and the auxiliary spark arrestor netting is secured thereover in any suitable manner, as by welding. The valve means comprises a valve plate 61 adapted to rest upon the opening with its edges overlapping the edges of the opening and suitably biased to resist lifting under normal con ditions. For this purpose the valve plate 61 may be suitably weighted in any suitable manner which may, for simplicity and durability, consist merely in selecting the valve plate of suitable thickness for the particular draft conditions encountered in the locomotive being so equipped. For compactness, the auxiliary opening and valve plate are preferably provided in the horizontal table plate 2|, and two such openings are preferably provided, one on each side of the exhaust nozzle i1. Guide brackets H are provided secured to and rising from the table plate around the edges of the valve plate 61 to guide and limit its movement from and to the auxiliary opening.

In accordance with another embodiment of our invention, shown in Fig. 6, more positive agitation of the netting is obtained responsive to pulsations of exhaust team. For this purpose we provide a cylinder 13 having a piston 15 from which a rod I! extends through the other end of the cylinder and is pivotally connected through a-link 19 to the net agitating lever 55. From the outer end of the piston a guide 8! extends laterally and slides upon a stationary guide bar 83. The other end of the cylinder is connected into the exhaust nozzle through a conduit 85, shown dotted. As each impulse of exhaust steam is discharged through the exhaust nozzle ll suiiicient back pressure is set up to actuate the piston which through the link 1!! throws the netting toward the smoke stack. Between pulsations of exhaust steam the netting falls back. The positive agitation set up by throwing the netting back and forth dislodges cinders and particles which wouid tend to accumulate and clog the air passages.

It is apparent that within the scope of our invention modifications and diiferent arrangements may be made other than herein disclosed, and the present disclosure is illustrative merely, the invention comprehending variations thereof.

We claim:

1. In a locomotive construction having a smoke box with an inlet, a smoke stack for discharging gases from said smoke box, and an exhaust nozzle disposed for discharging exhaust steam through said stack to move combustion gases from the inlet through to the stack, the combination of deflector means positioned within said smoke box between said inlet and said stack and embodying a restricted opening through which combustion gases flow, a spark arrestor netting, means for mounting said netting across said restrict-ed opening, said mounting means providing for a limited movement of said netting in the path of combustion gases for vibrating responsive to gas pulsations as the combustion gases are strained by said netting before being discharged; by: the smoke stack, said deflector means having. angauxiliary opening therein providing a, by-pass for combustion gases through said deflector means and around said movable netting, spark arrestor nettingv secured over said auxiliary. opening, and closure means normally closing said auxiliary opening andoperatable responsive to a predetermined diiferential of pressure to open to the smoke stack side for releasing-such pressure differential.

2. In a locomotive spark arrester, a smoke box, said smoke box havingan inlet forreceiving com.- bustion gases from a locomotive boiler, a smoke stack for discharging combustion gasesfrom said smoke box, the combination or deflector means positioned within said smoke box between said inlet and said stack and embodying a restricted opening through which combustion gases flow, an exhaust nozzle for discharging the exhaust steam through the smoke stack to induce-a draft through said smoke box from said inlet and out said stack, a spark arrestor netting positioned across said restricted opening for straining the combustion gases to restrict cinders and flre particles passing from the smoke box through the smoke stack, means mounting said transversely disposed netting movably in the path of combustion gases to permit movement of the netting between two extreme positions in the direction of said path, said netting being vibrated by pulsations of combustion gases acting directly thereon, said deflector means having an auxiliary opening therein providing a by-pass for gases through said deflector means and around said movable netting, and pressure responsive by-pass means covering said auxiliary opening for normally closing it and operating to open on the stackside thereof for releasing pressure on said netting.

3. In a locomotive construction having a smoke box with an inlet, a smoke stack for discharging gases therefrom, the combination of deflector means positioned in said smoke box for directing the flow of combustion gases through the smoke box from said inlet to the smoke stack and embodying a restricted opening through which combustion gases flow, spark arrestor netting mounted over said restricted opening, means supporting said netting to have a limited movement for vibrating in the direction of the path of gas flow diverted by said deflector means so that it may be vibrated or agitated by the direct action of pulsations of gas passing therethrough, said deflector means having an auxiliary opening therein providing a by-pass for gases through said deflector means and around said movab e netting, spark arrestor netting secured over said auxiliary opening, valve means normally disposed to close said auxiliary opening during the normal operation of the locomotive, and being operative to open said auxiliary opening when the pressure on the inlet side of said netting exceeds the pressure on the outlet side thereof by a predetermined amount.

4. In a locomotive construction having a smoke box, a smoke stack for discharging combustion gases from said smoke box, an exhaust nozzle disposed for discharging exhaust steam and creating a draft out through said stack, spark arrestor netting, means mounting said netting in the smoke box between the inlet and said stack, the combination of deflector means for directing the flow of combustion gases in a predetermined path through said netting, said deflector means having an auxiliary opening therein providing a by-pass-for gases through said do: flector means and around said netting, spark arrestor netting disposed. and secured over said auxiliary opening, a valve plate, guide means controllingv said valve platefor normally resting over said auxiliary opening and overlapping: the edges thereof, and said valve plate being suitably biased to resist lifting under normal conditions and being operative toopen said auxiliary opening when the pressure on the inlet side oi said netting exceeds the pressure on the outlet side thereof by a predetermined amount.

5. In combination in a locomotive construction having a smoke box having an inlet for admitting: gases, a smoke stack for. discharging admitted gases therefrom, an exhaust nozzle dis.- posed for discharging exhaust steam through said stack-to. create a draft in the usual manner, the combination of a movable spark arrestor net.- ting, mounting means supporting. said netting in said smokebox so that it may have a limited movement tomove between an upper and a lower position for vibrating directly responsive to gas pulsations, a deflector wall in said smoke box for diverting the combustion gases around a predetermined flow. path to pass through and be strained by. said. netting before being discharged by the smoke stack, said deflector wall having an auxiliary opening providing a bypass for gases through said deflector wall and around said movable netting, spark arrestor netting. disposed andsecured over said auxiliary opening, means normally closing said auxiliary opening and being operative to open said auxiliary opening when the pressure on the inlet side of said netting exceeds the pressure on the outlet side thereof bya predetermined amount, and blower means for projecting live steam to create a draft up said stack.

6. In a locomotive construction having a smoke box with an inlet and a smoke stack opening therefrom, the combination of deflector means for controlling the flow of combustion gases through the smoke box to the smoke stack and embodying a restricted opening through which combustion gases flow, said deflector means including a horizontal table plate arranged below said stack, an exhaust nozzle passing through said table plate in alignment with said stack, spark arrestor netting, means sup porting said netting across said restricted opening, said supporting means permitting said netting to move with the gas to an upper position and to fall back to'a lower position so that it may be vibrated or agitated by pulsations of gas passing therethrough, said table plate having two auxiliary openings therethrough on opposite sides of said nozzle and providing by-passes for gases through the horizontal table plate portion of the deflector means and by-passing said arrestor netting, spark arrestor netting disposed and secured over said auxiliary openings, two valve plates one resting over each of said auxiliary openings and" overlapping the edges thereof, said valve plates beingof suitable weights to resist lifting under normal conditions and being operative to open said auxiliary opening when the pressure on the inlet side of said netting exceeds the pressure on the outlet side thereof by a predetermined amount, and guide means for controlling and limiting the movements of said valve plates to and from said auxiliary openings.

7. In combination in a locomotive, a smoke box having an inlet for receiving combustion gases, a smoke stack for discharging combustion gases therefrom, an exhaust nozzle disposed for discharging exhaust steam and creating a draft from said inlet through said smoke box and out said stack, a spark arrestor netting, means movably supporting said netting in the path of gas flow and transversely thereto so that it may vibrate responsive to gas pulsation, deflector means for diverting the combustion gases to pass through and be strained by said netting before being discharged by the smoke stack, vane means, means movably supporting said vane means in and transversely to the flow path of combustion gases for movement therewith, and actuating means connecting said vane means to said movable netting for agitating said movable netting to dislodge particles of solid matter from the netting.

8. The combination in a locomotive in accordance with claim 7, wherein said deflector means is further characterized by having an auxiliary opening serving as by-pass for gases through said deflector means and around said netting, spark arrestor netting disposed and secured over said auxiliary opening, closure means normally closing said auxiliary opening and being operative to open said auxiliary opening when the pressure on the inlet side of said netting exceeds the pressure on the outlet side thereof by a predetermined amount.

9. The combination with a locomotive in accordance with claim 7 and further characterized by having a draft plate, means pivotally supporting said draft plate along one edge in a position transversely exposed to the pulsations of gases flowing through the smoke box for causing the other edge to be moved therewith, agitating means for vibrating said movable netting, and actuating means connecting the draft .plate to said net agitating means for vibrating the movable netting to dislodge particles of solid matter from the netting.

10. In a locomotive construction having a smoke box with an inlet for reception of combustion gases and a smoke stack opening therefrom, the combination of deflector means for directing the flow of combustion gases through the smoke 'box to the smoke stack and embodying a restricted opening through which combustion gases flow, spark arrestor netting, mean supporting said netting over said restricted opening to have limited movement in the gas stream diverted by said deflector means so that the netting is substantially transverse to said flow path and movable back and forth by the direct action of the pulsations of gas passing therethrough, vane means, means movably supporting said vane means transversely in the flow path of combustion gases for limited movement therewith, actuating means connecting said vane means to said netting for agitating said movable netting to dislodge particles of solid matter from the netting, said deflector means having an auxiliary opening therein providing a by-pass for gases through said deflector means and around said netting, spark arrestor netting disposed and secured over said auxiliary opening, a valve plate disposed over said auxiliary opening and overlapping the edges thereof, said valve plate being suitably biased to resist'opening under normal conditions and being operative to open said auxiliary opening when the pressure on the inlet side of said netting exceeds the pressure on the outlet side thereof by a predetermined amount, and guide means for controlling and limiting the movements of said valve plate to and from. said auxiliary opening.

11. In combination in a locomotive, a smoke box having an inlet for receiving combustion gases from a locomotive boiler, a smoke stack for discharging combustion gases from said smoke box, an exhaust nozzle for discharging the exhaust steam to the smoke stack to induce a draft from the inlet through said smoke box out the stack, a spark arrestor netting for straining the combustion gases flowing through the smoke box to restrict cinders and fire particles passing from the smoke box through the smoke stack, a movable spark arrestor netting, means supporting said netting so that it may have limited movement in the gas flow path to vibrate responsive to gas pulsations, deflector means for diverting the combustion gases to pass substantially transversely through and be strained by said netting before being discharged by the smoke stack, a draft plate, means pivotally supporting said draft plate along an upper edge in a position exposed transversely to the pulsations of gases flowing through the smoke box for causin the lower or suspended edge to be swung therewith, agitating means for vibrating said movable netting, and actuating means connecting the lower edge of the draft plate to said agitating means for vibrating the movable netting to dislodge particles of solid matter from the netting.

12. The combination with a locomotive having a smoke stack, a smoke box with an inlet for receivingbombustion gases and an outlet communicating with said stack, an exhaust nozzle disposed for discharging exhaust steam and creating a draft from said inlet through said smoke box and out said stack, deflector means for controlling the flow of combustion gases through the smoke box along a predetermined flow path to the smoke stack, spark arrestor netting, means supporting said netting transversely in said path to have a limited movement with the gas stream diverted by said deflector means so that it may be vibrated or agitated directly by pulsations of gas passing therethrough, actuation means responsive to the intermittent pulsations of exhaust steam, and means connected to said actuation means and operatively associated with said movable netting for agitating the netting by the operation of said actuation means.

13. The combination with a locomotive having a smoke stack, a smoke box with an inlet for receiving combustion gases and an outlet communicating with said stack, an exhaust nozzle disposed for discharging exhaust steam and creating a draft out through said stack, deflector means for controllingthe combustion gases to have a predetermined flow path through the smoke box to the smoke stack, spark arrestor netting, means supporting said netting transversely to said path and to have a limited movement with the gas stream diverted by said deflector means so that the netting is vibrated or agitated by pulsations of gas strained therethrough, a steam cylinder, a piston reciprocatively disposed therein, conduit means connecting from said nozzle into one end of said cylinder, and actuating means connecting from said piston through the other end of said cylinder to said netting for agitating the netting responsive to the pulsations of exhaust steam.

ALBERT B. HARRIS. GRANVILLE M. BAKER. 

